Part 2 (5.290Mb)

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Advisory Committee on Fishery Management ICES CM 1999/ACFM:S

REPORT OF THE

WORKING GROUP ON THE ASSESSMENT OF DEMERSAL STOCKS IN THE NORTH SEA AND SKAGERRAK

ICES Headquarters 5- 14 October 1998

PART20F3

This report is not to be quoted witbout prior consultation witb tbe General Secretary. The document is a report of an expert group under the auspices of the International Council for the Exploration of the Sea and does not necessarily represent the views of the Council.

International Council for the Exploration of the Sea Conseil International pour l'Exploration de la Mer

Palægade 2-4 DK-1261 Copenhagen K Den mark

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TABLE OF CONTENTS

Section Page

l INTRODUCTION ... 1

I.l Participants ... 1

1.2 Terms of reference ... 1

1.3 Data ... 2

1.3.1 Data sources roundfish and flatfish ... 2

1.3.1.1 Data on landings, age compositions, weight at age, maturity-ogive ... 2

1.3.1.2 Discard data used in the assessment.. ... 3

1.3.1.3 Natural mortality ... 3

1.3.1.4 Fleet and research vessel data ... 3

1.3.2 Data sources Norway poul and sandeel ... .4

1.3.3 Sampling levels and sampling procedures ... .4

1.3.3.1 Sampling levels in 1997 ... .4

1.3.3.2 Sampling procedures ... .4

1.4 Methods and software ... ? 1.4.1 XSA ... 7

1.4.2 Forecasts, sensitivity analysis and medium-term projections, Roundfish and flatfish ... ? 1.4.3 Catch predictions and medium term projections, Norway pout and sandeel.. ... 9

l.S Stocks and assessments ... 9

1.6 Biological reference points ... 9

l. 7 Summary of PA reference points ... l O Tables 1.3.3.1.1- 1.7.1 ... 11

2 OVERVIEW ... 16

2.1 Stocks in the North Sea (Sub-area IV) ... 16

2.1.1 Human consumption fisheries ... l6 2.1.2 lndustrial fisheries ... 18

2.1.2.1 Description offisheries ... 18

2.1.2.2 Stock impressions ... 18

2.1.2.3 By-catches ofprotected species ... l8 2.2 Overview of the stocks in the Skagerrak and Kattegat (Division l1Ia) ... l8 2.3 Stocks in the eastern Channel (Sub-area V!Id) ... 19

Tables 2.1.1- 2.2.1 ... .21

Figures 2.1.1- 2.3.1 ... 26

3 COD IN AREAS IIIA (SKAGERRAK), IV AND VIID ... 28

3.1 The Fishery ... 28

3.1. l ACFM advice applicable to 1997 and 1998 ... 28

3.1.2 Management applicable in 1997 and 1998 ... 28

3.1.3 The fishery in 1997 ... 28

3.2 Natura( Mortality, Maturity, Age Compositions, and Mean Weight at Age ... 29

3.3 Catch, Effort, and Research Vessel Data ... 29

3.4 Catch at Age Analysis ... 29

3.5 Recruitment Estimates ... 30

3.6 Historical Stock Trends ... 31

3.7 Short Term Forecast ... 31

3.8 Medium term projections ... .31

3.9 Long Term Considerations ... 32

3.1 O Biological reference points ... .32

3.11 Comments on the Assessment ... .32

Tables 3.1.1- 3.10.4 ... .34

Figures 3.1.1- 3.10.3 ... 78

4 HADDOCK IN SUB-AREA IV AND DIVISJON IIIA ... I04 4.1 Tbefishery ... l04 4.1.1 ACFM advice applicable to 1997 and 1998 ... ! 04

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Section

4.1.2 4.1.3

Page Management applicable to 1998 ... 1 04 Ca te hes in 1997 ... 1 04

4.2 Natura! mortality, maturity, age composition, mean weight at age ... ! 04

4.3 Catch, Effort and Research V esse! data ... l 05 4.4 Catch-at-age analysis ... 105

4.5 Recruitment estimation ... 106

4.6 Historical stock trends ... 106

4.7 Short-term forecast ... 106

4.8 Medium-term projections ... l07 4.9 Long term considerations ... 107

4.10.1 Choice ofB,. ... 108

4.10.2 Choice ofF,. ... 108

4.11 Comments on the assessment ... 108

Tables 4.1.1- 4.10.2 ... 109

Figures 4.4.1a- 4.10.5 ... 148

5 WHITING ... 168

5.1 Whiting in Sub-area IV and Division Vlld ... : ... 168

5.1.1 The fishery ... 168

5.1.1.1 ACFM advice applicable to 1998 ... 168

5.1.1.2 Management applicable to 1998 ... 168

5.1.1.3 Landings in 1997 ... 168

5.1.2 Natura! morta1ity, Maturity, Age compositions, Mean weight at age ... 169

5.1.3 Catch, Effort and Research V esse! Data ... 169

5.1.4 Catch-at-age analysis ... 169

5 .1.5 Recruitment estimates ... 171

5.1.6 Historical stock trends ... 171

5 .l. 7 Short term forecast ... 172

5.1.8 Medium term predictions ... 173

5.1.9 Long term considerations ... 173

5.1.10 Biological reference points ... 173

5.1.11 Comments on the assessment... ... l73 5.1.12 Definition of safe biologicallimits using target and limit reference points ... 174

5.2 Whiting in Division Illa ... l74 Tables 5.1.1.1- 5.2.1.1 ... 175

Figures5.1.4.1- 5.1.12.2 ...•... 215

PART2 6 SAITHE IN SUB-AREA IV AND DIVISION HIA ... 247

6.1 The fishery ... 247

6.1.1 ACFM advice applicable to 1998 ... 247

6.1.2 Management applicable to 1998 ... 247

6.1.3 Trends in landings ... 247

6.2 Natura! mortality, maturity, age compositions, mean weight at age ... 247

6.3 Catch, effort and research vessel data ... 247

6.4 Catch-at-age analysis ... 248

6.5 Recruitment Estimates ... 248

6.7 Short term forecas\. ... 249

6.8 Medium term projections ... 249

6.9 Long term Considerations ... 249

6.1 O Biological reference points ... 249

6.11 Comments on the Assessment ... 250

Tables 6.1.1- 6.10.2 ... 251

Figures 6.1.1- 6.10.4 ... 275

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Section Page

7 SOLE IN SUB-AREA IV 7 ... 294

7 .l The fishery ... 294

7.1.1 ACFM advice applicable to 1997 and 1998 ... 294

7.1.2 Management applicable to 1997 and 1998 ... 294

7 .1.3 Fleet developments ... 294

7 .1.4 Landings in 1997 ... 294

7.2 Natura! mortality, maturity, age composition, mean weight at age ... 295

7.3 Catch, effon and research vessel data ... 295

7.4 Catch at age analysis ... 295

7.4.1 Exploration of data ... -... -... , .. , .. , ... , ... : ... 295

7.4.2 Final XSArun ... 296

7.5 Recruitment estimation ... 296

7.7 Shon term forecast ... 297

7.7.1 Additional natura! mortality in the winter of 1995-1996 ... .. 297 7.7.2 Forecast. ... 298

7.7.3 Sensitivity analyses ... 298

7.8 Medium term projections ... 298

7.9 Long term considerations ... 299

7.1 O Biological reference points ... 299

7.11 Comments on assessment.. ... 300

Tables 7.1- 7.2.3 ... 301

Figures 7.1- 7.1.9 ... 342

8 SOLE IN DIVISJON VIID ... 361

8.1 The fishery ... 361

8.1.1 ACFM ad vice applicable to 1988 ... 361

8.1.3 Landingsin 1997 ... 361

8.2 Natura! mortality. maturity, age compositions and weight at age ... 361

8.3 Catch, effon and research vessel data ... 362

8.4.1 Data screening ... 362

8.4.2 Exploratory XSA runs ... 362

8.4.3 Final XSA run ... 363

8.5 Recruitment estimates ... 363

8.6 Historical Stock trends ... 364

8.7 Shon term forecast ... 364

8.8 Medium Term Projections ... 364

8.9 Long Term Considerations ... 365

8.10 Biological Reference Points ... .365

8.11 Comments on the Asscssment ... .365

Tables 8.1.1a- 8.10.3 ... 366

Figures 8.1.1a- 8.10.2 ... .409

9 NORTH SEA PLAICE ... .428

9.1 The fishery ... .428

9.1.1 ACFM advice applicable to 1997 and 1998 ... , ... .428

9.1.2 Management applicable to 1997 and 1998 ... .428

9.1.3 Fleet developments ... .429

9.1.4 Landings in 1997 ... .429

9.2 Age composition, natura! monality, maturity, weight at age ... .429

9.3 Catch, effon and research vessel data ... .430

9.4 Assessment. ... .431

9.4.1 Data exploration ... .431

9.4.2 Final assessment ... .431

9.5 Recruitrnent.. ... .431 iii

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Section Page

9.6 Historie stock trends ... .432

9.7 Short term projection ... 432

9.8 Medium tenn projection ... 433

9.9 Long tenn considerations ... 433

9.11 Comments on the assessment ... .433

Tables 9.1 - 9.30 ... .436

Figures 9.1- 9.19 ... .473

PART3 JO PLAICE IN DIVISION I!IA ... : ... .493

!O.l The fishery ... 493

!O.l. l ACFM advice applicable to 1998 ... 493

10.1.3 Landings in 1997 ... .493

10.2 Natura! mortality, Maturity, Age Compositions and Mean Weight atAge ... .493

10.3 Catch, Effort and Research V esse! Data ... .493

10.4 Catch at Age Analysis ... .494

l 0.5 Recruitment estimates ... 495

l 0.6 Long-tenn trends ... .495

10.7 Short-term forecast ... 495

10.8 Medium-tenn projections ... .495

10.9 Long-tenn considerations ... .496

10.10 Biological Reference Points ... .496

10.11 Comments on the assessment ... 496

Tables 10.1.3- 10.9.2 ... 497

Figures 10.2.1- 10.10.2 ... .519

Il PLAICE IN DIVISION VIID ... 536

!I.l The fishery ... 536

11.1.1 ICESadviceapplicableto 1998 ... 536

11.1.3 Trends in landings ... 536

11.2 Natura! mortality, maturity, age compositions and mean weight at age ... 536

11.3 Catch, effort and research vessel data ... 536

11.5 Recruit estimates ... 538

11.6 Historica1 Stock Trends ... 538

11.7 Short term forecast ... 538

11.8 Medium term predictions ... 539

11.9 Long term considerations ... 539

11.10 Biological reference points ... .539

Il. l l Comments on the assessment ... .539

Tab1es 11.1.1- 11.10.3 ... 541

Figures ll.l.l-11.10.1 ... .571

12 NORWAY POUT IN SUB-AREA IV AND DIVISION IIIA ... 592

12.1 The fishery ... .592

12.1.1 ICES advice applicable to 1998 ... .592

12.1.3 Catch trends ... 592

12.2 Natura! Mortality, Maturity, Age Composition and Mean Weight at Age ... 592

12.3 Catch, Effort and Research V esse! Data ... : ... 593

12.4 Catch-at-Age Analysis ... 593

12.5 Recruitment Estimates ... .594

12.6 Historical Stock Trends ... 594 iv

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Section Page

12.7 Short-Term Forecasts ... 594

12.8 Medium-Term Predictions ... 594

12.9 Long-Terrn Considerations ... 594

12.1 O Bio1ogical Reference Points ... .594

12.11 Comments on the Assessment ... 595

Tables 12.1.1 - 12.6.1 ... 596

Figures 12.4.1- 12.8.3 ... 614

13 SANDEEL ... ~ ... 624

13.1 Sandeel in Sub-area IV and Illa ... 624

13.1.1 The fishery ... 624

13.1.1.1 ACFM advice applicable to 1997 and 1998 ... 624

13.1.1.2 Management applicable to 1997 and 1998 ... 624

13.1.1.3 Catch trends ... 624

13.1.2 Natura! mortality, maturity, age composition, mean weight at age ... 624

13.1.3 Catch, effort and research vessel data ... 625

13.1.3.1 Calculation of the total international effort in the sandeel fishery ... 625

13.1.3.2 Research vessel data ... 625

13.1.4 Catch-at-age analysis ... 625

13.1.5 Recruitment estimates ... 626

13.1.6 Historical stock trends ... 626

13.1.7 Stochastic short and median term forecas\.. ... 626

13.1.8 Bio1ogica1 reference points ... 626

13.1.9 Comments on the assessmen\ ... 627

13.2 Sandeel at Shetland ... 627

13.2.1 Catch trends ... 627

13.2.2 Assessment ... 627

13.2.3 Management in 1998 ... 627

Tab1es 13.1.1.1- 13.1.8.1 ... 628

Figures 13.1.1.1- 13.1.7.1 ... 653

14 NORWAY POUT AND SANDEEL IN DIVISJON VIA ... 669

14.1 Overview of industrial fisheries in Division VIa ... 669

14.2 Norway Pout in Division Vla ... 669

14.3 Sandeel in Division VIa ... 669

14.3.1 Catch Trends ... 669

14.3.2 Assessment ... 669

Tables 14.2.1 -14.3.1.1 ... 670

Figures 14.2.1- 14.3.1.1 ... 671

15 DISCARDS ... 672

Tables 15.1- 15.2 ... 673

16 WORKING DOCUMENTS ... 674

16.1 References ... 674

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6 SAITHE IN SUB·AREA IV AND DIVISION DIA 6.1 The f"lshery

6.1.1 ACFM advice applicable to 1998

The stock was considered to be outside safe biological limits. ACFM therefore recommended that the fishing mortality should be reduced by 20% from the fishing mortality in 1996 (F,. = 0.50) in order to have a high probability of the spawning stock biomass being.close to safe biological.limits in the medium term. The landings in 1998 corresponding to this reduction are 97,000 t.

This stock is associated with the West of Scotland stock, both in terms of stock distribution and in terms of some of the major exploiting fleets. Trends in SSB and recruitment are similar in both stocks. The West of Scotland stock is also considered to be outside safe biologicallimits_

6.1.2 Management applicab1e to 1998

Management of saithe is by TAC and technical measures. The agreed TAC for saithe in IV and IIIa for 1998 is 97,000 t.

The minimum mesh size is 100 mm in IV and 90 mm in Skagerrak.

Minimum landing size is 35 cm in EU waters. In Norwegian waters the minimum landing size is 32 cm in IV, and 30 cm in Skagerrak.

6.1.3 Trends in landings

Recent nominal landings are given in tablc 6. L L Working group estimates are in Table 6. L2 and are plotted in Figure 6.LL Landings were high in the early 1970s, reaching a maximum of 320,000 t in 1976. Subsequently, landings declined to 114,000 t in 1979, also due lo the discontinuation in the fishery of the USSR. After lhat, the landings followed an increasing trend to reach 200,000 t in 1985. This increase is part! y due to good year classes coming into the fishery. After 1985 the saithe landings decreased to 88,000 t in 1990, and sincc then the landings have increased slightly.

In 1996 and 1997, the landings are cslimated to be 110,000 t and 103,000 t respectively. Small amounts of saithe are takcn as industrial by-catch, but most of the saithe is sorted out and delivered for human consumption. Since 1977, the average industrial by-catch has been 2,400 t. In later years no bycatch has been registrated, but in 1998 a bycatch of about 3000 t was registrated. The catch trends do not includc discards. The agreed TAC in 1997 was 115,000 l which is 8,000 t higher than the estimated catch.

Saithe is mainly taken in a directed trawl fishery which started in the beginning of the 1970s. The French, German and Norwegian catches made up about 75% of the total international catch in 1997.

6.2 Natura) mortality, maturity, age compositions, mean weight at age

Conventional values of natura! mortality rate, and maturity at age based on biological sampling are given in Table 6.2.1.

They have been assumed to be the same all ycars. Total international age compositions are given in Table 6.2.2. Data for 1996 were updaled with minor changes. Data for !997 were supplied by Denmark, Germany, France, Norway, UK (England) and UK (Scotland) amounting to about 95% of the landings. Estimates of discards are available on! y from the Scottish flect, and they are not representative for the total international catch, and not included in the asscssment.

The mean weights at age in the landings are given in Tablc 6.2.3. These are also used as stock mean weights. SOP corrections have been applied.

6.3 Catch, effort and research vessel data

The French database for the large trawler fleet (FRA TRB) has been modified relative to last year in two ways; by the exclusion of catches taken in the Norwegian sector, and by the exclusion of trips targeting deepwater species rather than saithe.

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Formerly, the FRATRB series included all catches taken by these vessels, including those taken in the Norwegian sector, for which no effort figures are available. These catches have now been excluded so both the catches and effort figures now refer on! y to the EU sector of the North Sea. This also applies to data for the freezer trawler f!eet (FRATRF) which are available for tuning for the first time.

Since 1991, some trips by the FRATRB vessels have been exploratory and have targeted deepwater species in the Northem North Sea. These trips have been excluded, using a criterion of a minimum of 10% of saithe per fishing day.

This modification has resulted in a reduction of less than l% in the annua! landings attributed to this fleet, but has reduced the effort by between 15 and 30% per year. Data are currently available to apply these modifications back to 1992, and the 1991 data have also been modified on the assumption that the proportion of effort targeting deepwatcr species was the same in 1991 as it was in 1993.

The fleets used for tuning the VPA are given in Table 6.3.1. The data from the French trawlers starts in 1990 and 1992 and contains the age groups 3 - 10. The data from the Norwegian trawlers starts in 1980 and contains the age groups 3 - 10. After the drop in effort in the period 1985 to 1990, the effort in recent years seems to have stabilised on half the leve!

of 1985. The Scottish research vessel indices start in 1982 and contains age 2 and 3, and the English indices start in 1977 containing ages 2 - l O.

6.4 Catch-at-age analysis

The method used to tune the VPA was XSA (v3.1), the same rnning configuration as last year. Preliminary runs were done with all fleets included. Diagnostics and plots of the residuals were inspected. Age 2 from all fleets showed very big residuals and very low r', and they were therefore excluded. In FRATRB age 9 had a negative slope, and the same bad age 7 and 8 in FRA TRF. Age 9 in ENGGFS showed also bad diagnostics. Following data were used for the final run:

FRA TRB 1990--1997 FRATRF 1992-1997 NORTRL 1980--1997 ENGGFS 1977-1997 SCOGFS 1982-1997

age 3-8 age 3-7 age 3--9 age 3-8 age 3

Plots of the residuals are shown in Figure 6.4.1, and plots of indices against VPA are shown in Fig 6.4.3. Last year catchability was dependent of stock size for age l, 2 and 3. However, in the runs this year the t-value for age 3 was so low that it was decided to run the tuning with constant catchability for age 3. Catchability was fixed for ages 7 and above as last year. The rnning were run with no taper over ten years. The age range used for VPA was l to lO (the plus group), and F for the oldest ages was shrunk to the mean of the 3 youngcr ages. The tuning results are given in Table 6.4.1, Table 6.4.2 gives the values of fishing mortality rates, and Table 6.4.3 gives the stock numbers estimated by tuning. The F shrinkage mean gives a high weight for age l and 2. The surveys get some weight for the ages 3 and 4. For the ages 5 to 7 the commercial fleets got most of the weight while on older ages thetwo commerclal tleets and the mean shrinkcr are sharing the wcights (Figure 6.4.2).

Because of the short time series of FRA TRF a retrospectivc analysis could only be run for two years backwards. The results are plotted in Figure 6.4.4. There is reasonahlc agreement for the two runs.

6.5 Recruitment Estimates

Some survey data were available, but RCT3 runs showed that the VPA mean was given about 90% of the weights. The Group therefore decided to use a geometric mean to estimate recruitiDent. All points in the left corner of the stOck- recruitment plot (Figure 6.9.1) are derived from the last decade. The geometric mean over the last ten years was therefore used for ages l and 2 in 1998 (year classcs 1997 and 1996). The year dass 1997 was estimated to !55 million at age l, and the year dass 1996 was estimated to 131 million at age 2. For the year classes 1998 and 1999 the GM of 155 millions was used.

6.6 Historical stock trends

Table 6.6.1 gives a summary of the trends in landings, fishing mortality, bioma" and recruitrnent as estimated by VPA.

These data are also plotted in Figure 6.1.1.

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Mean fishing mortality increased subsrantially from 1981 to 1986. Since then, it has decreased to a leve! of about 0.5.

Total biomass and spawning biomass show a continuous downwards trend until 1990 when they were on historically low levels. The present assessment shows a slight improvement of the stock since then.

6. 7 Short term forecast

Input dara for prediction are given in Table 6.7.1. Ages l and 2 are GM estimates. The period for calculations of mean exploiration pattern and mean weights is 1995 to 1997, and the fishing pattem were not scaled to F97. Geometric mean are used for the 1998 and the 1999 year classes. Results of the prediction are given in Table 6.7.2 and in Figure 6.7.1.

Input dara for a sensitivity analysis are shown in Table 6.7.1 and the results of this analysis are shown in Figures 6.7.2 and 6.7.3.

Maintenance of the status quo of fishing mortality in 1998 is expected to lead to landings of lll,OOO t in 1998 and 123,000 t in 1999. Spawning stock size is predicted to increase to 134,000 t in 2000.

Table 6. 7.4 shows the contribution of the different year classes in the catch in 1999 and the spawning stock in 2000. Half of the expected landings in 1999, and half of the predicted SSB in 2000 is made up of year classes for which GM recruitment is assumed.

The sensitivity analysis shows that the prediction of the yield in 1999 is mostly dependent of the fishing mortality levels in 1999 and 1998 and the estimation of the number of the 1995 year dass, together with its weight at age 4 and its relative fishing mortality age 4. The prediction of the spawning stock in 2000 is dependent of the estimates of number, weight, proportion mature and relative fishing mortality of the same year class together with the fishing mortality levels in 1998 and 1999. (Figure 6.7.2). The stock numbers of age 3 contributes to most of the variance in the prediction (Figure 6.7.2). It must be remembered that the ages l and 2 (year classes 1997 and 1996) are gcomctric mcans.

The prohability plots show that there is about a 75% probability that the spawning stock will remain below 150,000 t in 2000 if the status quo fishing mortality (0.50) is maintained (Figure 6.7.3).

6.8 Medium term projections

The input for these analyses is shown in Table 6.7.1 and Table 6.8.1, and the results are presented in Figure 6.8.1. All stock-recruit models available were examined. All models showed similar shape. The analysis described in Sec ti on 1.4.2 was used and the group decided to use the Ricker model. It was also decided to use an average over ten years for the stock- and catch weights. Using the status quo fishing mortality, the median landings is expected to increase and stabilise at about 140,000 t. The median spawning stock biomass will stay at the present leve! of about 130,000 t, and the probability for SSB to remain below 150,000 t is about 40%.

6.9 Long term Considerations

Figure 6.9.1 shows the stock-recruitment plot. The status qw F (0.50) is slightly above F ... (0.48). The input parameters for the yield and biomass per recruit are given in Table 6.9.1 and the results are shown in Table 6.9.2 and Figure 6.7.1.

6.10 Biological reference points

For saithe 150,000 t has been used as MBAL, and the SGPAFM has suggested this value as a B,.. The choice of MBAL was based on an indication of reduced recruitment below that value. The Group decided to use 150,000 tas B.,.. for saithe in the North Sea and Skagerrak. However, next year the West of Scotland stock will be included in the assessment and tltis may result in a different B,.. Biological reference points were estimated using the PA software. Input values are shown in Tables 6.7.1 and 6.8.1, and the results are shown in Tables 6.10.1 and 6.10.2 and Figures 6.10.1 and 6.10.2.

Figure 6. 10.3 indicate F..,

=

0.44, F "''"

=

0,46 and F,.,.,

=

0,47. The probability of being below B,. in 2007 is sensitive to small changes in F between 0.4 and 0.45. Given the precision with which current values of F can be estimated, the Working Group proposes an F of 0.40 as F ,..

Figure 6.10.4 shows the history of F₄ versus SSB. In the last 14 years SSB has been below B,. and also above F ,...

The stock may be considered to be outside safe biological limits.

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6.11 Comments on the Assessment

This year's assessment is consistent with last year's assessment. However, for the 1996 year dass and onwards GM(86- 95) recruitment is assumed, and the year class 1995, which is important in the prediction, is not well estimated. The forecast should therefore be treated with caution.

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N V.

Table 6.l.J Nominal catch (in tonnes) of Saithe in Sub-area IV and Division Illa. 1986-1997, as ofticially reported to ICES.

Country 1986 1987 1988 1989 1990 1991 1992 1993 1994

Bdgium 16 4 60 13 23 29 70 113 130

Denmark 10,343 7,928 6,868 6,550 5,800 6,314 4,669 4,232 4,305¹

Faroe Islands 224 691 276 739 1,650 671 2,480 2,875 1,780¹

Francc: 43,958 38,356 28,913 30,761¹^'² 29,892¹^'² 14,795¹^'² 9,061¹ 15,258¹ 18,220¹^'²

Genna••Y 22,277 22,400 18,528 14,339 15,006 19,574 13,177 14,814 10,013

Netherlands 134 334 345 257 206 199 180 79 18

Norway 67,341 66,400 40,021 24,737 19,122 36,240 48,205 47,669 47,042

Pol and 495 832 l ,016 809 1,244 1,336 1,238 937¹ !51

Swedeu 1,987 1,732 2,064 797 838 1,514 3,302 4,955 5,366

UK (Eng!.& Wales) 4,480 3,233 3,790 4,012 3,397 4,070 2,893 2,429 2,354

UK (Scotland) 15,520 11,911 10,850 9,190 7,703 8,602 6,881 5,929 5,566

USSR 116³

Total reported to IC ES 166,775 153,821 112,731 92,204 84,881 93,460 92,156 99,290 90,337

Unreported landings -3,882 -4,414 -6,132 -172 3,199 5,093 343 5,316 12,256

Landings as used by WG 162,873 149,407 106,599 92,032 88,080 98,553 92,499 104,606 102,593

TAC 240,000 173,000 165,000 170,000 120,000 125,000 110,000 93,000 97,000

1Prdiminary.

2lndudes lla(EC), llla-d(EC).

~lndudes Estonia.

1995 1996 1997

228 !57 254

4,388 4,705 4,513

3,808 617 158

11,224¹ 12,227 19,658¹^'² 12,093 Il ,567 12,581

9 17 40

53,293¹ 55,382 46,484¹

592 365 822

1,891 1,771 1,592 2,522 2,864 2,556 6,341 5,848 6,329 96,389 95,520 94,987 17,171 14,826 8,339 113,560 110,346 103,326 107,000 111,000 115,000

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252

TABLE 6.1.2; Saithe in IV and Ill, North Sea and Skagerrak Annual weight and numbers caught, 1967 to 1997.

---

l

^Year

l

Wt. ('OOOt) INos. (millions)

l

1---1---1---1 1967

1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997

l

Min.

l

Mean

l Max.

78 104 115 222 253 246 226 273 278 320 196 135 114 120 123 166 16 9 198 200 163 14 9 107 92 88 99 92 105 103 114 110 103 78 157 320

54 62 66 142 176 176 16 9 165 189 310 121 97 68 72 70 115 112 167 208 157 166 93 75 73 93 71 78 BO 75 78 78 54 118 310

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Table 6.2.1 Natural Mortality (M) and maturity at age

YEAR ¹⁹⁶⁷

AGE Nat Mor Mat.

.2000 .0000

2 .2000 .0000

3 .2000 .0000

4 .2000 .1500

5 .2000 .7000

6 .2000 .9000

7 .2000 1.()()()() 8 .2000 1.()()()()

9 .2000 1.0000

+gp .2000 1.()()()()

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Table 6.2.2 Catch numbers at age Numbers*10"*-3

YEAR 1967

AGE

o

2 8494 3 15277 4 13335 5 13597 6 2035 7 1141 8 200 9 154

+gp 108

TOTALNUM 54342 TONSLAND 78480

SOPCOF% 100

YEAR AGE

+gp TOTALNUM

TONSLAND SOPCOF%

YEAR AGE

2 3 4 5 6 7 8 9

1968 172 3783 20788 18944 11987 5402 281 116

94 87 61654 104002 100 1978 1 1215 2 16503 3 30972 4 24935 5. 16771 6 2616 7 849 8 790 9 607

+gp 2165

TOTALNUM 97421 TONSLAND 134829

SOPCOF% 100

YEAR AGE

+gp TOTALNUM

TONSLAND SOPCOF%

254

2 3 4 5 6 7 8 9

1988 10 5158 26865 22887 32693 2777 1016 406 446 351 92608 106599 100

1969 36 1764 28252 13063 9559 7103 5170 685 547 79 66257 114758 100 1979 907 16787 14504 13022 10031 7991 2437

577 349 1333 67938 114363 100 1989 3642 9125 14870 25063 10934 9552 1182 481 262 305 75415 92032 100

1970 234 2228 34392 74326 13194 11529 3654 1596 278 144 141576 222100 100 1980 1276 23095 14159 11399 8338 6086 5189 956 418 1486 72402 120293 100 1990 291 4240 35037 15888 10119 3896 2246 495 148 205 72565 88080 100

1971 594 10773 68424 53348 30846 3650 3783 2481 1574

536 176011 252618 100 1981 5309 18195 22267 6362 6151 3265 2994 3173 504 1863 70083 122518 100 1991 334 11761 42313 26941

6293 2974 1286 706 267 241 93116 98553 100

1972 379 20189 40162 62290 23108 20779 3363 2790 1550 1445 176056 245879 100 1982 1932 28263 27405 38946 7934 5410 1761 1210 846 794 114502 165977 100 1992 290 5865 16626 30543 11772 2826 1409 631 461 327 70749 92499 100

1973 4416 31275 47388 32955 24967 15228 7998 1689 1165 1927 169008 225770 100 1983 270 32798 23363 17980 25161

4903 4380 1333 929 819 111936 168884 100 1993 139 7578 34742 17978 10758 2798 1407 1406 746 915 78468 104606 100

1974 3947 16150 61201 31387 12123 20080 13734 4308 988 1094 165011 273466 100 1984 59 34455 75449 29769 12081 12330 1357 1113 279 467 167379 198001 100 1994 102 6761 16516 38061 12097

3897 821 274 375 682 79585 102593 100

1975 312 71766 50672 23406 9005 6706 12650 8650 3304 2347 188819 278126 100 1985 226 7191 129042

52613 11827 3543 2397 496 295 519 208147 199534 100 1995 97 3012 26588 24379 13409 3204 3104 566 464 636 75459 113560 100

1976 235 31335 199669 50339 9902 5137 3317 4845 3003 2128 309910 319933 100

1986 89 6477 48517 82843 11422 3986 1549 987 260 555 156685 162873 100

1996 316 7467 9757 37988 11052 7172 2910 716 173 374 77927 110346 100

1977 2015 12891 22890 52270 13082 4753 3218 3062 3522 3780 121484 196185 100

1987 786 29143 28906 90314 12037 1789 1031 786 649 483 165925 149407 100 1997 26 11411 12382 17639 29120 3339 2434 921 264 258 77794 103326 100

(17)

Table 6.2.3 Catch weights at age (kg)

YEAR 1967

AGE

.0000 2 .6790 3 .8920 4 1.3070 5 2.0770 6 3.1300 7 3.7180 8 5.2880 9 5.8350

+gp 7.9440

SOPCOFAC .9998

YEAR AGE

+gp SOPCOFAC

YEAR AGE

+gp SOPCOFAC

YEAR AGE

+gp SOPCOFAC

2 3 4 5 6 7 8 9

1968 1969 5010 .4510 .7720 .5780 1.291

o

^.9620

1.6520 1.6080 1.9720 2.2630 3.0170 2.6990 4.0690 3.5690 4.4590 4.3350 6.4260 5.1570 7.4970 6.1310 1 .0001 1.0001

1978 1979 .3530 .4340 .5200 .3890 .7810 1.0800 1.2940 1.5900 2.1200 2.2190 3.2100 3.071

o

4.4660 3.9660 4. 7840 5.1280 5.3090 5.9470 6.7460 7.1700 1.0001 1 0001

1988 1989 .4290 .4260 .6120 .7270 .731

o

^.9000

.9310 1.0220 1.3620 1.4010 2.6320 1.9330 3.6690 3.8310 4.6270 4.8220 5.6540 6.3110 7.2010 84540 1.0000 .9999

1970 .4340 .6970 .9310 1.4420 2.0730 2.7080 3.5980 4.4200 5.6150 6.6590 .9998

1980 .2530 .4110 .9050 1.8120 2.3700 2.9750 4.0470 5.0440 5.8120 7.3220 1.0001

1990 .2160 .6990 8450 1.2030 1.5610 2.1950 3.1580 4.5840 6.0440 8.3660 1.0002

1971 .4950 .6090 .8380 1.3570 2.2030 3.0070 3.8040 4.6350 5.1680 5.6910 1.0001

1981 .2740 .5850 .9370 1.8590 2.6940 3.5290 4.4700 5.4240 6.9070 8.3490 1 0000

1991 .4410 .5260 .7780 1.1510 1.7420 2.3590 3.1240 4.0700 5.8960 7.6650 1.0000

1972 .3040 .5100 .7430 1.1580 1.8970 2.3640 3.8690 4.1840 4.5430 6.1200 .9999

1982 .2490 .4980 1.0870 1.5660 2.4970 3.1440 3.9580 4.9080 5.6060 7.7480 1.0001

1992 .6290 .6130 .9510 1.1760 1.5740 2.1840 3.6280 4.2610 5.2840 6.2820 1.0000

1973 .1540 .3920 .7800 1.4070 1.5750 2.5430 3.3390 4.6570 4.5020 6.0460 .9999

1983 .4180 .4550 .9820 1.7010 2.1180 3.0580 3.5330 4.4320 5.3360 6.9480 1.0000

1993 3300 .7190 .8930 1.2400 1.7310 2.6120 3.1320 3.9430 5.0090 6.7450 1.0001

1974 .2680 .4940 .8490 1.5560 2.4890 2.7290 3.3530 4.3860 5.5380 7.5250 1.0000

1984 .1810 .4820 .7720 1.6000 2.2700 2.6450 3.7150 4.5240 5.8970 7.7200 .9999

1994 .2800 .6910 9070 11130 1.5750 2.3780 3.5340 4.6500 6.5660 8.2190 .9999

1975 .1980 .4940 8870 1.4970 2.4780 3.2750 3.6840 4.1900 5.4810 7.4190 .9999

1985 .1430 .5080 .6480 1.2420 1.8690 2.6110 3.1760 4.5550 5.3310 7.8900 1.0000

1995 .5140 .7750 1.0250 1 .2750 1.7870 2.5310 3.5290 4.6480 5.0930 7.5690 1.0001

1976 .4610 .5010 .6900 1.3020 2.1750 3.0360 4.0070 4.3250 4.9810 6.7680 1.0002

1986 .5180 .5250 6690 1.0050 1.6700 2.2690 3.5430 4.2400 5.7540 7.9860 .9999

1996 .2530 .4750 .9500 1.1900 17740 2.3450 2.8910 4.6430 5.9230 8.2070 .9999

1977 .4290 .4160 .7530 1.2510 1.9000 3.0970 4.1460 4.5510 4.7790 6.2570 1.0000

1987 3710 .4060 .6510 .8520 1.7880 2.9420 3.8200 4.8680 5.4840 7.0380 1.0001

1997 .4220 .4250 .9040 1.1410 1.4440 2.5410 3.5280 4.5000 6.1390 8.8020 .9998

255

(18)

Teble 6.3.1 SAITHE IN THE NORTH SEA & SKAGERRAK; 1967 ^- 1997 ^> Tuning data.

105 FRATRB

1990 1997 l l .00 l .00

3 8

158U .000 3311 .000 2417 .000 1381 . 000 305 . 000 290 .000 33. 000 12697 .000 1316. 000 2481. 000 736 .000 380. 000 134. 000 66 .000

7902 .000 695. 000 1465. 000 530. 000 80. 000 27 .000 8 .000

14412. 000 3808 .000 2229. 000 1264. 000 120. 000 lO. 000 lO .000 14125. 000 1739. 000 3686. 000 1422. 000 447. 000 40 .000 5 .000

14739. 000 3082. 000 1670. 000 943 .000 234 .000 74. 000 26 .000

16043. 000 894 .000 4282. 000 1041. 000 532 .000 107 .000 24. 000

13009 .000 1075. 000 1879. 000 3171.000 199 .000 88. 000 17. 000

FRATRF 1992 1997 l l . 00 l . 00

3 7

1832 .000 215. 000 427 .000 120.000 17. 000 6 .000

8059 .000 1917 .000 1139 .000 412.000 23 .000 2 .000

8082 .000 863 .000 1665. 000 559.000 165 .000 15. 000

8844. 000 1308. 000 788. 000 494. 000 128. 000 43 .000

7824 .000 379. 000 1790. 000 345. 000 182 .000 37 .000

6767 .000 635. 000 1148. 000 1644. 000 68 .000 29 .000 NORTRL

1980 1997 l l . 00 l . 00

3 lO

18317. 000 18 6 .000 1290. 000 658. 000 980. 000 797 .000 261 .000 60 .000 82 .000

28229 .000 88. 000 844. 000 1345. 000 492 .000 670. 000 699. 000 119. 000 64. 000

47412. 000 6624. 000 12016. 000 2737 .000 2112 .000 3 41. 000 234 .000 19. 000 77 .000 43 099 .000 4401 .000 4963 .000 8176 .000 1950. 000 2367. 000 481 .000 357 .000 B4 .000 47803 . 000 20576 . 000 732 8. 000 2207 .000 3358. 000 433 .000 444. 000 106 .000 51 .000

66607.000 27088.000 21401. 000 5307 .000 1569 .000 63 7 .000 56. 000 46 .000 4.000

57468.000 5297.000 29612 .000 3589 .000 818 .000 393 .000 122 .000 25 .000 33.000

30008.000 2645.000 18454. 000 2217. 000 290. 000 235 .000 201. 000 198 .000 64.000

18402.000 3132.000 2042 . 000 2214. 000 141 .000 157 .000 74 .000 13 4 . 000 43.000

17781.000 649. 000 212 6. 000 835. 000 694 .000 309 .000 154. 000 65. 000 7 .000

10249.000 804. 000 781. 000 924. 000 519 .000 203 .000 63 .000 12 .000 3 .000

28768 .000 14348. 000 4968. 000 1194. 000 518 .o o o 203 .000 51 .000 56. 000 l .000

35621 .000 3447. 000 9532 .000 4031 .000 1087 .000 465 .000 165 .000 109. 000 6 .000

24572 .000 7 635 .000 4028. 000 2 87 8. 000 1018. 000 526. 000 365 .000 252 .000 252 .000

30628. 000 3939 .000 16098 .000 4276 .000 l26 .000 251. 000 n .000 203 .000 21. 000

32489. 000 4347 .000 93 66 .000 5412 .000 833. 000 1644. 000 273. ·JOD 203 .000 104. 000 40400. 000 3790 .000 1442 9 .000 4414 .000 2765. 000 1144. 000 1.39. 000 16 . 000 :.3 . 300 31077. 000 2395 .000 4538. 000 8638. 000 1249 .000 300 .000 280. 000 68 . 000 28 . 000 ENGGFS

1977 19'18

l 0.5 J. 75

3 8

l 484 . 9103659 867 .5753049 52 .61707317 21 .41067073 17 . 212 5 13 . 43414634 l 57 .35640244 34 . 9847561 93 .01280488 6 .203963415 l .446036585 l. 446036585

l 104. 9853659 160 .3079268 116 .6935976 69. 45640244 84. 15 4 .78902439

l 179. 5993902 164. 1484756 91.2402439 17. 95884146 41 .46859756 13 . ) 875

l 119 .7634146 113 .1640244 248.6716463 o 68. 66341463 73. 60792683

2121. 102439 1921 .409451 105.1875 28 . 92073171 5. 504268293 9 .096036585 547 .2198171 257.7210366 312.3439024 41 . 37530488 23 . 94115854 24 .16280488 4643. 564024 1284.033841 364.6344512 503 .5286585 39. 46280488 37 .64359756 2710. 968902 758.7960366 121.1871951 59 . 98719512 68 .98993902 lO .9152439 1708 .744207 695.4042683. 133.5018293 50 .65792683 17 .07256098 31 . 29969512

255. 1204268 1710.991159 225.0219512 52 .47713415 19 . 91798711 l. 632621951 l 786 .5954268 238.8292683 251.9835366 22 . 67012195 11 .10182927

'.

^586585366

l 17B .407622 161.0698171 45.1070122 52 .4027439 7 . 995426829 3 . 871646341 l B72 . 7112805 83.54054878 49 . 49176829 21 .05640244 30. 29237805 12 . 38018293

426 .470426f! 97.18597561 22. 12926829 19. 6847561 4. 524695122 lO .19054R78 94 .231886 230.7028947 42 . 71642991 15 .92468507 4. 664634146 lO .86705977 l 1091 .482846 413 .0936746 83 . 55333691 33 .267'i5562 623224337 9 .756432592 l 12 3 .26253C2 75. 18091664 55. 1554543 49 .260'::8697 9 . 4317 8772.4 4. 7:!.5893862 l 1366. 474582 262. 1934468 98 . 05146073 33 .37007505 20 . 76018494 6. 372062 996 l 296. 6486867 691 .8661217 72 . 65210399 43 .622.:11823 17 .70168856 3. 10975609R

449. 9998883 287 .5840927 452. 022246 24. 02372018 22 .19545693 8. 594545698 53 . 79478245 3 53 . 7594925 126 .5773251 123 .313'1899 ^]. 312181 7c:1 9.312181721 SCOGFS

1982 1997

l l o. 5 0.75

3 3

1370

l 370

l 26470

l 40140

l 43180

l 1700 l 1430 l 1320 l 4010 l 3180 l 1840 l 7890 l 1390

l 13920

l 4050 l 3670

256

(19)

Table 6.4.1. SAITHE IN THE NORTH SEA &. SKAGERRAK : 1967 • 1997 CPUE data from file saiivef9.dat

Catch data for 31 years. 1967 to 1997. Ages 1 to 10.

Fleet First Last First last

yea' ^year age age

FRATRB 1990 1997 3 8

FRATRF 1992 1997 3 7

NORTRl 1988 1997 3 9

ENGGFS 1988 1997 3 8

SCOGFS 1988 1997 3 3

Time series weights :

Tapered lime weighting not applied Catchability analysis :

Catchability dependent on stock size for ages c: 3 Regression type

=

C

Minimum or 5 points used for regression

Survivor eslimates shrunk to the populalion mean ror ages < 3 Catchability independent of age ror ages :>= 7

Terminal population estimatian :

Survivor estimates shrunk tow.ards the mean F of the final 5 years or the 3 oldest ages.

S.E. of the mean to which the estimat es are shrunk

=

.500 Minimum standard error far populatian

estimates derived from each fleet = .300 Prior weighting not applied

Tuning converged after 26 ilerations Regression weights

Fishing mortalilies

Age 1988 1989

1 o ^0.021

2 0.074 0.076

3 0.363 0.314

4 0.624 0.691

5 1.001 0.705

6 0.57 0.952

7 0.64 0.51

8 ^0.478 ^0.732

9 0.525 0.66

XSA populalion numbers (Thousands) AGE

YEAR 2

1988 1.69E+05 8.02E+04 1989 1.97E+05 1.38E+05 1990 1.39E+05 1.58E+05 1991 2.17E+05 1.14E+05 1992 1.36E+05 1.77E+05 1993 2.78E+05 1.11E+05 1994 1.02E+05 2.27E+05 1995 1.19E+OS 8.33E+04 1996 2.43E+OS 9.73E+04 1997 6.93E+04 1.98E+OS Estimated populalion abundance at 1st Jan 1998

1990 0.002 0.03 0.46 0.656 0.675 0.589 0.611 0.417 0.517

3 9.75E+04 6.10E+04 1.05E+05 1.26E+05 8.23E+04 1.40E+05 8.43E+04 1.80E+05 6.55E+04 7.29E+04

1991 0.002 0.122 0.465 0.794 0.596 0.425 0.391 0.39 0.416

4 5.45E+04 5.55E+04 3_65E+04 5.43E+04 6.46E+04 5.23E+04 8.32E+04 5.40E+04 1.23E+05 4.48E+04

Alpha Beta

o 1

o l

0.5 0.75 0.5 0.75

1992 1993 1994 1995 1996

0.002 0.001 0.001 0.001 0.001

0.037 0.078 0.033 0.041 0.089

0.253 0.321 0.244 0.178 0.18

0.739 0.477 0.705 0.69 0.417

1.042 0.637 0.699 0.58 0.799

0.592 0.762 0.5 ^0.397 0.721

0.365 0.675 0.526 0.999 0.776

0.338 0.771 0.26 0.876 0.661

0.48 0.868 0.476 0.954 0.737

5 6 7 8 9

5.71E+04 7.06E+03 2.37E+03 1.18E+03 1.21E+03 2.39E+04 1.72E+04 3.27E+03 1.02E+03 5.99E+02 2.28E+04 9.67E+03 5.43E+03 1.61E+03 4.04E+02 1_55E+04 9.50E+03 4.39E+03 2.41E+03 8.66E+02 2.01E+04 6.99E+03 5.09E+03 2.43E+03 1.34E+03 2.52E+04 5.80E+03 3.17E+03 2.89E+03 1.42E+03 2.66E+04 1.09E+04 2.22E+03 1.32E+03 1.09E+03 3.37E+04 1.08E+04 5.43E+03 1.07E+03 8.33E+02 2.22E+04 1.54E+04 5.96E+03 1.64E+03 3.66E+02 6.65E+04 8.17E+03 6.1SE+03 2.24E+03 6.91E+02

O.OOE+OO 5.67E+04 1.52E+05 4.85E+04 2.07E+04 2.81E+04 3.67E+03 2.83E+03 1.00E+03 Taper weighted geometric mean of the VPA populalions:

2.08E+05 1.74E+05 1.27E+05 7.33E+04 3.31E+04 1.39E+04 6.51E+03 3.01E+03 1.42E+03 Standard error of the weighted Log(VPA populations) :

0.5307 0.4957 0.5195 0.5001 0.5261 0.6845 0.7612 0.8201 0.8773 Lo~ catchabilifv residuals.

1997

o

0.066 0.208 0.571 0.662 0.601 0.576 0.605 0.549

257

(20)

Table 6.4.1 continued Fleel : FRATRB

Age 1988 1989 1990 1991 1992 1993 ¹⁹⁹⁴ 1995 1996 1997

3 99.99 99.99 0.55 -0.32 -0.16 0.44 0.15 -0.11 -0.42 -0.12

4 99.99 99.99 0.36 0.27 0.02 -0.07 0.09 -0.32 -0.4 0.06

5 ^99.99 ^99.99 ^0.14 ^0.09 ^0.16 ^0.03 ^0.15 -0.6 -0.07 0.1

6 ^99.99 ^99.99 ^0.02 ^0.41 ^-0.3 ^-0.23 ^0.36 ^-0.37 ^0.15 ^-0.04

7 ^99.99 ^99.99 1.15 0.71 -0.58 -1.56 0.14 0.01 0.11 O.o1

8 99.99 99.99 0.11 0.6 -1.07 -1.43 -1.54 0.54 -0.14 -0.61

9 No data for !his fleet at !his age Mean log catchability and standard error of ages with catchability independent of year class strenglh and con slant w.r .l. time

Age 3 4 5 6 7 8

Mean Log q -13.3703 -12.3445 -12.2128 -12.7785 -13.3682 -13.3682

S.E(log q) 0.3502 0.262 0.2524 0.2918 0.8121 0.972

Regression statis.tics :

Ages with q independent of year class strength and constant w.r.t. time.

Age Slepe 1-value lntercept RSquare No Pts Reg s.e MeanO

3 ^0.77 ^0.778 ^12.94 ^0.65 8 0.28 -13.37

4 ^1.78 ^-2.008 ^13.4 ^0.52 8 0.39 -12.34

5 1.13 -0.506 12.48 0.71 8 0.3 -12.21

6 0.69 1.308 11.63 0.74 8 0.19 -12.78

7 ^0.59 0.782 11.34 0.38 8 0.49 -13.37

8 4.55 -0.816 36.14 O.D1 8 3.96 -13.81

Fleet :FRATRF

Age 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997

3 ^99.99 ^99.99 ^99.99 ^99.99 ^0.22 ^0.43 0.1 -0.37 -0.47 0.1

4 99.99 99.99 99.99 99.99 0.4 o ^O.D1 ^-0.4 -0.4 0.38

5 99.99 99.99 99.99 99.99 0.42 -0.23 0.05 -0.45 -0.17 0.38

6 99.99 99.99 99.99 99.99 0.1 -0.82 0.4 0.02 0.28 0.03

7 ^99.99 ^99.99 ^99.99 ^99.99 0.08 -1.89 0.41 0.68 0.47 0.25

8 No data for this fleet at !his age 9 No data for !his fleet at !his age Mean tog catchability and standard ener of ages with catchabilily independent of year class strength and constant w.r.t time

Age 3 4 5 6 7

Mean Log q -13.4618 -12.5036 -12.4957 -13.2602 -14.0652

S.E(Log q) 0.3474 0.3546 0.3473 0.4299 0.9485

Regression statislics :

Ages wilh q independent of year class strenglh and constant w.r.t. time.

Age Slope 1-value lntercepl RSquare No Pts Reg s.e Mean Q

3 0.95 0.111 13.37 0.59 6 0.37 -13.46

4 1.89 -1.129 13.75 0.29 6 0.65 -12.5

5 0.85 0.448 12.17 0.69 6 0.32 -12.5

6 0.52 2.233 11.3 0.85 6 0.17 -13.26

7 0.54 0.792 11.46 0.43 6 0.53 -14.07

258